The Report by the Juries includes an evaluation of the state of the art, many with extended essays about various technologies. On photography the jury write:

"That Photography will have a great tendency to depress mediocrity, we may safely predict; that, from the date of the general application of Photography to the illustration of scenes daily passing around us, will commence a new era in pictorial representation; that it will greatly enrich us with authentic records of works, that would otherwise pass away without a single detaining effort from the hand of the artist, owing to their being of too transient a nature to admit of the accuracy and detail necessary to give it value in future ages;—is attested by the various and excellent representations which we now possess ..."

A full copy of the Report by the Juries, which may be of interest if your ancestor was involved in one of the areas discussed, is at http://goo.gl/JKzru